Matt Freeman, managing consultant at car valuation firm cap hpi, told the Daily Mail: “Hitting the 2021 environmental targets for CO2 reduction would be a significant challenge without the likely decline in diesel.

“Therefore it is imperative that diesels continue to command a substantial share of the new car marketplace.

“If consumers, with no option of transitioning to hybrid or EVs, switch to petrol the environmental impact is clear – their CO2 emissions would likely rise between three per cent and 23 per cent according to model.”